O.S.B.M.

The Order of Saint Basil the Great (O.S.B.M. Latin: Ordo Sancti Basilii Magni, Portuguese: Ordem de São Basílio Magno, Ukrainian: Чин Святого Василія Великого, Chyn Sviatoho Vasyliia Velykoho) also known as the Basilian Order of Saint Josaphat is a monastic religious order of the Greek Catholic Churches that is present in many countries and that has its Mother House in Rome (Santi Sergio e Bacco degli Ucraini). The order received approbation on August 20, 1631. Its monks, brothers, and priests work primarily with Ukrainian Catholics and are also present in other Greek-Catholic churches in central and eastern Europe.

The order is based upon the ascetic writings of Saint Basil the Great (329-379, in accordance with the Rule of St Basil laid down by him and later developed by Saint Theodore the Studite (760-826), Saint Theodosius of Kiev (†1074), Saint Josaphat Kuntsevych (1580-1623) and the Metropolitan of Kiev Joseph Benjamin Rutsky (1574-1637).

Monastic life began to develop in Ukraine in the times of Saint Vladimir the Great (980-1015), when the first monks settled in the caves near Kiev led by Saints Anthony and Theodosius. After the Mongol invasions in the 13th century the monks fled to western lands of Halych-Volhynia and the Grand Duchy of Lithuania, spreading Eastern Monasticism there. After the Eastern Rite Ruthenian Church (in modern-day Belarus and Ukraine) has re-affirmed its communion with the Catholic Church in the Union of Brest in 1596. The monasteries living according to the rules of St. Basil and St. Theodore Studite, previously undergoing a period of laxity and decline, were reformed by the initiative of Saint Josaphat Kuntsevych and Joseph Benjamin Rutsky started in the monastery of the Holy Trinity in Vilnius. Following this reform in 1617 the individual monasteries united into a single congregation under a Protarchimandrite directly subject to the Metropolitan, similar to the path Western Rite monasticism took during the Middle Ages. In 1739 a second congregation was formed by monasteries in Halychyna and in 1744 both congregations were united in the Ruthenian Order of St. Basil the Great by Pope Benedict XIV.

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